1. Field of the Invention
The present invention relates to a disk device, particularly to a disk device on which a rotary disk exchanger mechanism is mounted.
2. Description of the Related Art
In this type of disk device, a rotary tray having a plurality of disk setting sections in the circumferential direction is mounted on a slide tray which is taken in and out from a device body. A disk which is set at each disk setting section on the rotary tray is chucked by a chucking mechanism at a disk scanning position when rotation of the rotary disk is stopped. An operation of taking in and out the slide tray, an operation of rotating the rotary tray so as to move a disk, which is set at a predetermined disk setting section, to a disk scanning position and an operation of chucking on and off at the disk scanning position are all conducted by utilizing power generated by motors.
In this type of disk device, it is conventional that a rotary operation of the rotary tray and an operation of chucking on and off by the chucking mechanism are conducted by one motor. However, three operations including a rotary operation of the rotary tray, an operation of chucking on and off by the chucking mechanism and an operation of taking in and out the slide tray are not conducted by one motor.
On the other hand, in Japanese Unexamined Patent Publication No. 10-49959, there is a description of a disk player in which three operations including a rotary operation of the rotary tray, an operation of chucking on and off by the chucking mechanism and an operation of taking in and out the slide tray are conducted by one motor.
This disk player is composed as follows. Power generated by one motor is transmitted to a planetary gear mechanism including an internal gear, the diameter of which is large, and a planetary gear revolving while rotating round its own axis being meshed with the internal gear. Revolution of the planetary gear of the planetary gear mechanism is transmitted to a Geneva gear arranged on a rotary tray, so that the rotary tray is intermittently rotated. At the same time, in cooperation of a cam plate, which is revolved by the revolution of the planetary gear, with an elastic member, a chucking operation by the chucking mechanism is controlled being turned on and off. When the planetary gear of the planetary gear mechanism is locked at a predetermined position so as to stop the revolution of the planetary gear, rotation of the planetary gear round its own axis is converted into a linear motion of a rack used for taking in and out the slide tray. Due to the foregoing, the slide tray can be taken in and out. When the chucking mechanism is changed over from a state of chucking off to a state of chucking on, a cam protrusion provided in the chucking mechanism is disengaged from the cam plate. In accordance with that, a turn table of the chucking mechanism lifts a disk set on the rotary tray upward, by an elastic force of the elastic member. Due to the foregoing, the chucking mechanism is changed over from a state of chucking off to a state of chucking on.
According to the above former conventional disk device, two motors are required. One is a motor which rotates the rotary tray and chucks on and off by the chucking mechanism. The other is a motor which takes in and out the slide tray. Therefore, the manufacturing cost is raised.
On the other hand, according to the latter disk device described above, three operations including a rotary operation of the rotary tray, an operation of chucking on and off by the chucking mechanism and an operation of taking in and out the slide tray are conducted by one motor. Therefore, the number of motors, which are required for the disk device, can be reduced compared with the above conventional disk device. Therefore, it is possible to reduce the manufacturing cost necessary for the motor.
However, the latter disk device uses the planetary gear mechanism provided with the internal gear. Further, in the disk device, the chucking mechanism is turned on and off in cooperation of the cam plate with the elastic member. Therefore, the following problems may be encountered in the disk device.
In the planetary gear mechanism, the internal gear and the planetary gear are combined with each other, and when rotation of the planetary gear meshed with the internal teeth of the internal gear is transmitted, the planetary gear is rotated and revolved. Accordingly, there is a restriction in suppressing a gear ratio of the internal gear to the planetary gear, and the freedom of selecting the gear ratio is remarkably limited.
Since the chucking operation is turned on and off in cooperation of the cam plate with the elastic member, when a state in which the chucking mechanism is turned off is changed over to a state in which the chucking mechanism is turned on, the turn table of the chucking mechanism lifts the disk set on the rotary tray from its setting position in a rush manner. Therefore, when the disk is chucked (clamped) by the chucking mechanism, an impact shock is generated. Thus the disk interferes with the rotary tray by the shock, which causes a problem. Further, the following problems may be encountered. Since an elastic force generated by the elastic member fluctuates, when the disk is chucked by the elastic force generated by the elastic member so that recording or playback can be conducted, the rotating disk oscillates and interferes with the rotary tray. This deteriorates stability of recording or playback.